The founders of Facebook, Google, and WhatsApp sold billions in stock this year

Microsoft founder Bill Gates reacts as he plays table tennis at a Berkshire Hathaway sponsored reception in Omaha, Nebraska May 4, 2014 as part of the company annual meeting weekend.
REUTERS/Rick Wilking
Bill Gates topped a 2015 list of the biggest insider sellers that is dominated by tech company founders.

Google co-founders Sergey Brin and Larry Page sold more than $1.6 billion (£1 billion) of their company stock between them, while former Twitter CEO Evan Williams sold $359 million of shares in the company he helped set up.

Sqoop doesn't say whether these are preplanned sales or not. The raw data doesn't mean the executives are bailing on their businesses.

Tech insiders hold six spots on the top-10 list, with Sergey Brin appearing twice after setting up Google's new umbrella company, Alphabet. WhatsApp founder Jan Koum is new to the list from the first half of the year.

Over the 12 months, Sqoop has tracked the amount of money company insiders have made from stock sales as disclosed to the US Securities and Exchange Commission. The list of the top sellers is compiled by totaling the top 200 insider sales for the year and then separating out institutional investors to get company insiders.

Company insiders can sell off stock as long as they inform the market and only use information available to other investors to make their decision.